Verify the ink composition. Ink consists of pigment, a vehicle for holding the pigment and a modifier to keep ink from breaking down. Offset inks must contain a vehicle of soya or linseed oil, or a synthetic chemical, such as the combination of phenol and formaldehyde. The composition of the offset ink will determine how well the pigment stays uniform when passing through the offset press to paper.
Test the tack quality of the offset ink. Tack quality confers the stickiness of the ink as it transfers from press rollers to ink plate and blanket. Turn the inkometer on. Measure a minimal amount of ink onto the rollers of the inkometer. The tack grade of the ink will display on the inkometer dial. Acceptable ink grades for older offset presses range from 13 to 20. Modern presses function well with lower tack grades.
Mark a sample of printing paper with a wide black line. Spread a small dab of offset ink with an ink knife across the black line. How well the ink covers the black line determines its opacity. Opacity hides the color or paper beneath. Opaque offset ink qualifies for use in an offset printer.